When Mercedes-AMG previewed what was to become the confusingly named GT 4-Door Coupe, the concept exhibited in March 2017 at the Geneva Motor Show rocked a hybrid powertrain with a twin-turbo 4.0-litre V8 and an electric motor. The conventional engine was installed in it’s usual place at the front and worked together with the e-motor at the back to enable an immense combined output of 805 bhp.

The folks from Affalterbach have since confirmed plans to put the hybrid powertrain into a production model, and now it looks like we won’t have to wait much longer. The GT 4-Door Coupe in the 63 S guise is already the most powerful Mercedes production model outside of the Project One, but the rumoured GT73 will take things to a whole new level by packing around 800 bhp. According to Autocar, it’s due for a release as early as next year.

Gallery: Mercedes-AMG GT Concept

The British magazine actually has a few spy shots (see source link above) of an interesting prototype featuring an intricate electrical system that likely indicates the test vehicle had a hybrid powertrain. Not only that, but Autocar learned from spy photographers the test prototype drove away without making any engine noise, so it must’ve been in electric mode.

The decision to slap on the “73” badge would make sense since Mercedes has used it in the past for several special cars, like the super-rare SL73. We might also see it on flagship versions of the G-Class and next-generation S-Class since trademark filings from February 2018 revealed nameplates such as a “G73” and an “S73.” The “GT73 4Matic+” moniker has also been registered by the three-pointed star, and it will represent the company’s answer to the Porsche Panamera Turbo S E-Hybrid with “only” 671-bhp.

It is believed the extra hardware compared to the GT63 S won’t add a considerable amount of weight to the GT73, which will allegedly lower the 0-62 mph from 3.2 to only 3.0 seconds. Aside from boosting the saloon’s acceleration, the hybrid component will also enable the car to offer a pure electric mode for as much as 31 miles.

When it will eventually arrive on the market, expect the GT73 to command a significant premium over the £135,550 GT63 S. For reference, the Porsche Panamera Turbo S E-Hybrid starts off at £140,132.